Reliable data on the risk of transmission of N. gonorrhoeae would enhance our understanding of the importance of host defenses against gonorrhea and would aid in the evaluation of prophylactic measures. This paper examines the risk of transmission of gonorrhea from infected female to male and the role that variables such as race, prophylaxis and amount of exposure play in the development of gonococcal urethritis. Volunteer crew members of a large naval vessel were followed prospectively as a cohort to study their risk of acquiring gonococcal infection during a four-day liberty period in the Far East. At the same time the prevalence of N. gonorrhoeae was determined in a population of females to whom the sailors were exposed. The calculated risk of transmission per exposure with an infected partner was .19 for whites and .53 for blacks. A statistically significant relationship was noted between the risk of transmission of gonorrhea and both the number of partners and the frequency of sexual intercourse. Further, the increasing infection rate with increasing numbers of exposures in men who had a single sex partner suggests that the majority of men are in fact susceptible to gonorrhea if the quantity of exposure is sufficient.

In a prospective evaluation of antibiotic prophylaxis against gonorrhea, 1080 men were given 200 mg of oral minocycline or placebo after sexual intercourse with prostitutes in a Far Eastern port. Later, at sea, gonococcal infection was detected in 57 of 565 men given placebo and 24 of 515 men given minocycline (P less than 0.001). Minocycline prophylaxis completely prevented infection by gonococci susceptible to 0.75 microgram or less of tetracycline per milliliter, reduced the risk of infection or prolonged the incubation period in men exposed to gonococci susceptible to 1.0 to 2.0 micrograms per milliliter, but did not prevent infection or prolong incubation in men exposed to gonococci resistant to 2.0 micrograms. Minocycline did not increase the proportion of asymptomatic infections. Minocycline prophylaxis would probably have limited effectiveness as a public-health measure because of the tendency to select resistant gonococci.

No abstract

No abstract

In a study of serodiagnosis of syphilis, the authors compared the specificities and sensitivities of two hemagglutination tests, a sheep-erythrocyte test (MHA-TP) and a trukey-erythrocyte test (TPHA), with those of the Fluorescent Treponemal Antibody-Absorption (FTA-ABS) test. In tests of sera from 935 patients without syphilis, the MHA-TP, TPHA, and FTA-ABS tests were reactive for 0.96, 0, and 1.3% respectively. The false-positive results were usually transient and not associated with underlying illness. For the 68 patients with syphilis, the MHA-TP test was as sensitive as the FTA-ABS test in all stages except untreated primary disease. The TPHA test appeared to be undersensitive, and testing of follow-up sera from persons with latent syphilis showed unexplained conversion of false-negative TPHA results to reactive results. Reproducibilities of the two hemagglutination tests were comparable. The MHA-TP test is a valuable confirmatory test for syphilis. Further study is needed before the use of the TPHA test can be recommended.